Resolves several rare problems including:#123022 segfault with certain maildir usage#113492 after expunge, dovecot hangs fetchmail if new e-mail came in

Note that #115284 the SSL related crash is not fully resolved. Rather than crash when entropy is depleted, dovecot silently fails. This remaining issue is Fedora specific and may require patching of the FC1 kernel or openssl in order to resolve in a future update.---------------------------------------------------------------------